It is now official – we are running Cloud Linux on all our production boxes and we can confirm that we are out of its beta stage. Given that, it seems appropriate to describe what are our impressions with this software suite.
The first impression that Cloud Linux leaves is related to the astonishing easiness that things happen with. In its essence, Cloud Linux is actually a super-modified Linux kernel and upgrading your Linux kernel has never been easier. It literally takes couple of shell commands executed in consequence, a quick reboot and you are ready to go. The couple of shell commands install the Linux kernel, set it up to boot on next startup and also enable a very fancy statistics module available to all users in the cPanel.
As soon as the server gets back online with the Cloud Linux kernel, the first thing which even a non-seasoned system administrator will notice is the load average changed forever. If you used to see numbers greater than 10-15, with Cloud Linux kernel it would be a real disaster if you see numbers above 6-7. In most time, the load will not climb up higher than 3. In normal operation states, it will remain between 1 and 3.
The philosophy that Cloud Linux preaches, stands for equal resources usage by every single user on the server. A state of mind that the entire shared hosting industry has been seeking for years is now accomplished. Achieving that is now easier thanks to LVE – the essential component that Cloud Linux steps on, in order to divide system resources effectively between users.
We have all heard (and seen in practice) the story how a single website, totally unsuitable for shared hosting, due to resource demands, consumes all the available CPU, IO, memory resources, web server child processes, etc. Here LVE (Limited Virtual Environment) comes handy – it is the layer between the request to virtual host (website, in practice) and the system that serves it (the kernel). Mediating between these two fundamental layers, LVE makes sure that a certain website will abide to the policies predefined by the system administrator and will not run the entire server out of resources. Think of LVE as a separate server in the main one, in which your website operates. Your LVE includes your own CPU, memory and processes boundaries, so does the other LVEs. This is a great leap towards avoiding the case where a very heavy website is exceeding these boundaries and affects other ones hosted on the same server, only the heavy website will slow down, without causing latency issues to other customers that shared the same physical server and its resources.
Cloud Linux is software appliance that is created from experts in the web hosting industry for this very industry. The team that worked initially on this project and continue to develop it in time, has a long time experience in the web hosting fields and, as it seems, knows what a web hosting company needs to make Customer experience better. Definitely it is a great improvement in terms of performance and allows every company that uses it, including TMDHosting provide better service. Last, but not least Cloud Linux comes handy with a great statistics plugin that is accessible directly from cPanel and allows a non-techie Customer to see their LVE usage at a glance, including where, how and why boundaries are being hit.
This article is part of the upcoming Cloud Linux series, which will continue to develop and will be published at the TMDHosting blog. Hopefully you have enjoyed it. Stay tuned for more.